The States Reorganisation Act,1956
Section 22. Joint meetings of Zonal Councils
(1) Where it is represented to the Zonal Council for any zone that a matter in which a State included in that zone and one or more States included in any other zone or zones have a common interest should be discussed at a joint meeting, it shall be lawful for the Zonal Councils concerned-
(a) To meet at such time and place as the Chairman thereof may, in consultation with each other, appoint in this behalf; and
(b) To discuss the said matter at such joint meeting and make recommendations to the Governments concerned as to the action to be taken on that matter.
(2) The Central Government may make rules for regulating the procedure at joint meetings of the Zonal Councils.